In industrial and/or consumer product applications, some electronic means are required to detect different faces on a three dimensional object for the purposes of identification and/or automating sorting, for example to identify the 2 faces of a tile, or to identify the 6 individual faces on a cube and etc. RFID (Radio Frequency Identification) technology can be used to identify the different faces of the object. In the RFID method, RFID data chip with different ID codes can be put onto the underside of each face of the 6 faces on a cube, such that a RFID reader/decoder can be used to read and to decode the RFID data chip on each of the faces. Alternatively, bar code labels, each with a different bar code, can be applied to a surface, and a bar code scanner can be used to read the bar code applied on this surface for identification.
Use of the RFID method requires a separate RFID data chip for each surface of the object, therefore the cost for using the RFID technology is relatively high. In addition the data chip needs a mechanical assembly process in order to be placed onto each of the faces, therefore errors can be introduced during the assembly process. For example, the data chip can be put wrong onto an incorrect surface, not to mention the extra labor cost for the mechanical assembly.
Similarly, in the case of the bar code label technology, it is necessary to apply a bar code label onto a surface. Again this requires an additional assembly process which can add costs and is possible to introduce errors, not to mention other problems such as a case that the bar code label is relatively easily torn off from a surface, making the identification to be a failure.
Moreover, a bar code is an optical machine-readable representation of data, which shows data of the object to which it attaches. Generally the bar code represents data by varying the widths and spacing of parallel lines in black and white. When the bar code is printed on a surface of an object, it is less aesthetic.
Therefore there is a need for providing a new technology for the identification of a surface, which can reduce the costs and avoid the errors to increase the precision of reading the code.